IP address range of the app store

Hi,

we're trying to setup an open Wifi for an exhibit booth, which users can use to download our iPhone app and surf our corporate website (but nothing else....restrictions, restrictions, I know ;().
To make this happen, we must restrict the IPs of outbound connections. Unfortunately, I don't know what to put in for the App Store. Which IPs do I need to clear so that users can use the iPhone's AppStore app?

The exhibit will take place in Germany, but the App will be available in numerous (country) AppStores. All of these must be accessible. Is there somekind of IP range or pattern?

Regards,

Sebastian